To protect tourist economy, resorts invest in seaweed-control business

AlgaeNova retention barriers hold back seaweed in the Dominican Republic. - Photo: AlgaeNova

For Caribbean communities dependent on idyllic beaches for their tourism product, sargassum seaweed influxes can seem like an existential crisis.

In July, Jamaica’s Minister of Tourism Edmund Bartlett estimated that sargassum clean-up had cost the Caribbean US$120 million in 2018. Along Mexico’s Caribbean coast, where many luxury resorts have been overwhelmed by the foul-smelling seaweed, he estimated a 35% drop in tourism.

The economic impact of sargassum and its potential to send tourists packing has put much of the region on high alert.

To protect the paradisiac image of Caribbean beaches, sargassum control has risen as another pillar of the region’s tourist industry – and in Mexico, securing sargassum-control contracts has become competitive.

From June to December 2018, the Quintana Roo Secretariat of Ecology and Environment reported more than CI$13.5 million (about MX$323 million) in sargassum-control contracts from federal, state and municipal entities.

“We want to get back to the paradise that was Cancun – the paradise with white sand beaches and a sea in seven shades of turquoise,” said Fernanda Diaz, a project manager for Goimar, one of many companies working to install sargassum-retention barriers in Mexico.

“Right now, we have two [colours], between green and brown.”

On a June afternoon, Diaz and her colleague Edgar Capricho visited Grand Bahia Principe Resort in Tulum to begin setting up a mile of barrier nets set back from the coast.

Before the team began installation, the resort’s beachfront had been overrun by seaweed, with more than 100 labourers working to remove the masses by shovel, wheelbarrow and tractor. As fast as the men could move the seaweed away, more washed ashore, leaving guests wading through the tangled algae.

Goimar hopes to reduce the number of sargassum workers at the resort to around 22 who will work in two shifts to manage the nets 24 hours a day.

“A 30-foot boat will take in the collected sargassum from the contention net and hand that over to the [wave runners],” Capricho explained.

“The trained personnel will do a check every 15 minutes to make sure there is no marine life, like sea turtles, trapped in the nets.”

Unlike many other sargassum-barrier companies, Goimar does not harvest the seaweed. Instead, workers take the sargassum out to the sea and redirect it back to the open ocean.

The idea, Capricho said, is to work with the natural life cycle of the plant.

“We want to be ecologically responsible, so that the cycle of the sargassum isn’t interrupted and it stays in the sea. We don’t want it to land on the beach where it decomposes and is moved to a landfill,” Capricho said.

Canadian company Ocean Cleaner has also entered the Mexican sargassum market, partnering with hotel developer Grupo Vidanta in the Riviera Maya. The company has installed around a mile of barrier in the Mexican Caribbean and reported plans to install additional barriers in Mexico and the Dominican Republic.

Sargassum retained in their barriers is collected using the company’s Sargatrailers that carry the seaweed from Sargaboats, which are equipped with conveyor belts to harvest algae from the water.

Once a trailer is full of seaweed, it is detached from the boat and transferred to dry land for processing.

“Grupo Vidanta is more of a laboratory where once we collect the sargassum, it is actually dried up and it is mixed in with their green cuttings and they actually do what is called bio-compost with it. They use it for their grounds. They’ve got hectares and hectares,” said Ocean Cleaner’s Francesco Maselli.

Like many companies in the algae-barrier business, Ocean Cleaner is experimenting with practical uses for its seaweed haul. Given the shear quantity of sargassum floating in, the plants cannot simply be left in the retention nets.

“You have to have a system where you relieve the pressure from the barriers, or else it will accumulate and once it does accumulate, it will either go right over or right under with the current,” Maselli said.

In addition to the sargassum compost in Mexico, Ocean Cleaner is also working with researchers in Quebec to explore the possibility of sargassum-based fertiliser or plastic.

In the Dominican Republic, another collection company is also dreaming up novel uses for seaweed. AlgaeNova’s Frederick Gonzalez said his employer’s boat and barrier system can collect up to 30 tons of sargassum every 45 minutes.

He describes the operation’s sargassum cleaner as a sort of floating car wash. Along the Punta Cana coast, AlgaeNova has installed more than 2.5 miles of barrier, where another conveyor system harvests the seaweed for removal.

“In 2016-2018, we woke up to this reality and the next machine we designed was planned to collect 370 tons a day,” Gonzalez said.

Now the company has 24 workers who monitor the nets full time and harvest the seaweed for processing.

Like Ocean Cleaner, AlgaeNova is in search of the most cost-efficient and practical use of its sargassum stockpile.

Through private partnerships, the company is testing a wide variety of applications, from the more common sargassum fertiliser to the unconventional idea of sargassum plates and utensils.

AlgaeNova has begun working with Poland’s Biotrem, a producer of wheat bran tableware, to develop biodegradable seaweed utensils.

The company is also exploring development of sargassum biofuel.

“There are possibilities to take advantage of sargassum,” Gonzalez said. “We have to compare the options with the commercial viability, the level or investment and technology, and the volume that can be consumed. We need to find a solution that can consume 300 tons a day.”